阅读说明：本技术 介质检测装置 (Medium detection device ) 是由 A.博贾斯基 R.阿德纳 L.乌勒曼 W.费希特 于 2018-06-18 设计创作，主要内容包括：本发明涉及一种用于检测介质的装置。这些更具体地特征在于,可以简单地检测到介质和/或可以确定或监视介质的性质。为此,包括加热装置和在正向上操作的至少一个pn结的加热传感器、以及包括在正向上操作的至少一个pn结的参考传感器彼此隔开距离地布置。所述加热装置和所述pn结连接到控制装置,所述控制装置根据介质的热性质,来确定介质的存在和/或至少一种性质。(The present invention relates to a device for detecting a medium. These are more particularly characterized in that the medium can be simply detected and/or properties of the medium can be determined or monitored. To this end, a heating sensor comprising a heating device and at least one pn-junction operating in a forward direction, and a reference sensor comprising at least one pn-junction operating in a forward direction are arranged at a distance from each other. The heating means and the pn-junction are connected to a control means which determines the presence and/or at least one property of the medium on the basis of a thermal property of the medium.)

1. A device for detecting a medium, characterized in that a heating sensor (1) comprising a heating means and at least one p-n junction operating in a forward direction, and a reference sensor (2) comprising at least one p-n junction operating in a forward direction are spaced apart from each other, in that the heating means and the p-n junction are connected to a control means, and in that the control means are control means which find out the presence and/or at least one property of the medium on the basis of a thermal property of the medium.

2. The device according to claim 1, characterized in that the control device is a control device which ascertains the difference between the forward voltage of the p-n junction between the medium heated by the heating sensor (1) and the unheated medium at the reference sensor (2).

3. The device according to claim 1 or 2, characterized in that the heating means are in each case at least one resistor (R1) and/or a p-n junction.

4. Device according to one of the preceding claims, characterized in that the p-n junction is the base-emitter path of a diode (D) or a transistor.

5. The device according to one of the preceding claims, characterized in that each of the p-n junctions is connected to an input of a differential amplifier (5) and an output of the differential amplifier (5) is connected to the control means.

6. The device according to one of the preceding claims, characterized in that the heating sensor (1) and the reference sensor (2) comprise a plurality of p-n junctions connected in series and spaced apart from each other.

7. The arrangement according to one of the preceding claims, characterized in that the p-n junction is connected to the grid via a DC-DC converter (4), wherein the DC-DC converter (4) is or comprises at least one constant current source.

8. Device according to one of the preceding claims, characterized in that the heating sensor (1) and the reference sensor (2) are designed as fingers.

9. Device according to one of the preceding claims, characterized in that, at least in some regions, the component comprising the p-n junction and the heating device is located as a heating sensor (1) on a first branch of a component carrier (6) designed in a U-shape and the component comprising the p-n junction is located as a reference sensor (2) on a second branch of the component carrier (6) designed in a U-shape.

10. Device according to one of the preceding claims, characterized in that at least a branch of the component carrier (6) in the U-shaped design comprising the specific component is embedded in plastic or located in a housing (7).

11. Device according to one of the preceding claims, characterized in that the means for detecting a medium comprise a DC-DC converter (4), a differential amplifier (5), the heating means, and the p-n junction in connection with a data processing system as the control means, as sensors for detecting the medium.

12. Device according to one of the preceding claims, characterized in that the means for detecting a medium are means for detecting the filling level of the medium in a container.

13. Device according to one of claims 1 to 11, characterized in that the means for detecting a medium are means for detecting the flow of the medium.

14. Device according to one of claims 1 to 11, characterized in that the means for detecting a medium are means for detecting the state of aggregation of the medium.

15. Device according to one of claims 1 to 11, characterized in that the means for detecting a medium are means for detecting the concentration of a substance as the medium in a binary system.

16. Device according to one of claims 1 to 11, characterized in that the means for detecting a medium are means for detecting the oil level in a transmission.

17. Use of a device for detecting a medium according to one of claims 1 to 16.

Technical Field

The present invention relates to a device for detecting a medium.

Background

In particular, according to publication DE 102007003860 a1, a device for detecting a medium is known as a sensor for detecting a liquid state. The sensor comprises a sensor element as a resistor between ceramic layers, which is a heating element and which also changes its resistance depending on the temperature of the sensor element and thus of the medium on the sensor element.

Publication DE 19741892 a1 describes a method and a device for determining the quantity and quality of a liquid. The fill level is ascertained with a temperature-dependent resistor element. The resistor element is heated via the supply of current and simultaneously the voltage across the resistor element is measured, wherein at least two voltage values are utilized in order to ascertain the filling level.

Publication DE 4436395C 1 describes a filling level sensor which comprises a plurality of voltage dividers which are distributed over the area of the filling level to be measured. If the fill level exceeds or falls below the voltage dividers, each of which includes a negative temperature coefficient thermistor and a positive temperature coefficient thermistor, a significant jump in the output signal occurs. The thermistor is coupled to a particular medium, in this case fuel and air.

The sensitivity of these solutions is limited in particular by the specific material of the resistor.

Publication DE 102008012503 a1 discloses a water sensor comprising a solenoid valve. This relates to an assembly for monitoring the water level in a fuel filter, in particular a diesel fuel filter. The basis is a fill level tube associated with the water collection container of the diesel fuel filter. At least one given height is provided with a measuring rod which transmits a signal if the water level reaches the measuring rod. Therefore, only the conductive substance can be detected.

Publication GB 2222705 a discloses a decompression housing for determining the air flow from a device having a decompression, said decompression housing comprising a sensor for detecting the flow rate of the air, which is connected to a control device. For this purpose, an anemometer device comprising two adjacently arranged electronic components can be utilized, wherein one of these components is mounted on the heating means. The two components are connected to a circuit for detecting the temperature difference of the components and thus the air speed. No determination of the medium is provided.

Publication DE 2950762 a1 discloses an apparatus for detecting the presence of a free-flowing medium by means of a first temperature-dependent semiconductor device, which effects heating of the apparatus above ambient temperature and which is immersed in the free-flowing medium, wherein its temperature drops. Furthermore, a second temperature dependent semiconductor device is provided, the temperature of which is lower than the temperature of the first device. By detecting the change in the difference, it can be concluded that there is a free flowing substance. A zener diode operating in reverse is utilized for this purpose.

Publication US 4677850 a describes a semiconductor component for detecting a flow of a medium. In this case, the first semiconductor chip includes a first temperature detector, and the second semiconductor chip includes a heating element and a second temperature detector, wherein the second semiconductor chip is arranged in the vicinity of the first semiconductor chip. The semiconductor chips are arranged one after the other in the direction of the medium flow. The semiconductor element is provided for detecting the air flow rate of intake air, in particular of an internal combustion engine.

Publication CN 1986107738A discloses an element for performing detection as a sensor comprising at least one p-n junction, wherein a large current is utilized for self-heating and a small current is utilized for detection. The p-n junction is utilized for heating and for sensing temperature so that there is thermal coupling in the element itself. This affects the detection and therefore the sensitivity of the element and thus the measurement accuracy is limited.

Publication EP 2037233 a1 describes a detector for determining the presence of a fluid. The detector includes a probe including a thermistor, and a temperature sensor for measuring a temperature of the thermistor. Determining the presence or identity of the fluid surrounding the probe based on a time component of supplying current to the thermistor to maintain the thermistor substantially at a predetermined temperature. The use of thermistors and their temperature measurement limits the sensitivity and measurement accuracy.

Disclosure of Invention

The problem addressed by the present invention is that of easily detecting the medium.

This problem is solved by the features mentioned in claim 1. Advantageous embodiments are described in the dependent claims.

The means for detecting a medium are distinguished in particular by the fact that the medium can be detected simply and/or that a property of the medium can be determined or monitored.

For this purpose, a heating sensor comprising a heating device and at least one p-n junction operating in a forward direction, and a reference sensor comprising at least one p-n junction operating in a forward direction are spaced apart from each other. The heating means and the p-n junction are connected to a control means, which is a control means that ascertains the presence and/or at least one property of the medium from the thermal properties of the medium.

The device for detecting a medium is based on the principle of thermal measurement, wherein the thermal properties of the medium are utilized. This is done statically or in time sequence by ascertaining the temperature difference between the heated sensor and the unheated reference sensor.

The p-n junction operates in the forward direction and measures the forward voltage and thus the on-state voltage. This can be done via the supply of a constant current by means of a constant current source. The forward voltage is temperature dependent, so that different voltage values start when a temperature change occurs and depending on the corresponding medium. By means of the control device, the voltage value can be assigned to the specific medium or the property of the medium. In this case, the measurement advantageously takes place by means of the heating sensor and the reference sensor in relation to each other, so that the ambient temperature (in particular the resultant temperature of the medium surrounding the device) is not incorporated into the measurement result.

In an embodiment of the invention, the control means is a control means to find the difference between the forward voltage of the p-n junction between the medium heated by the heated sensor and the unheated medium at the reference sensor.

In an embodiment of the invention, the heating means are in each case at least one resistor and/or a p-n junction. In both cases, electrical energy from the applied voltage and from the flowing current is converted into thermal energy. Advantageously, so-called known SMD components can be utilized for this purpose.

In an embodiment of the invention, the p-n junction is advantageously the base-emitter path of a diode or a transistor.

In an embodiment of the invention each of said p-n junctions is connected to an input of a differential amplifier, and an output of said differential amplifier is connected to said control means. For this purpose, the control device can advantageously be a data processing system, in particular a microcontroller.

In an embodiment of the invention, the heating sensor and the reference sensor comprise a plurality of p-n junctions connected in series and spaced apart from each other. The voltage drops at the series-connected p-n junctions are cumulative and therefore different fill levels can be assigned via the position of the p-n junctions.

In an embodiment of the invention, the p-n junction is connected to the grid via a DC-DC converter, wherein the DC-DC converter is or comprises at least one constant current source.

In an embodiment of the invention, the heating sensor and the reference sensor are advantageously designed as fingers.

In an embodiment of the invention, at least in some regions, the component comprising the p-n junction and the heating device is located as a heating sensor on a first branch of the component carrier designed in a U-shape, and the component comprising the p-n junction is located as a reference sensor on a second branch of the component carrier designed in a U-shape. The legs are spaced apart in a finger-like manner and are arranged parallel to each other and simply extend into the medium during use of the device. For this purpose, the fingers may advantageously be components of a circuit board on which components of the device are arranged and connected to one another via strip conductors.

In an embodiment of the invention, at least the branches of the component carrier, which are designed in a U-shape, including the specific components, are embedded in plastic or located in a housing.

In an embodiment of the invention, said means for detecting a medium comprise a DC-DC converter associated with a data processing system (in particular a microcontroller as said control means), a differential amplifier, said heating means, and said p-n junction as sensors for detecting said medium.

In an embodiment of the invention said means for detecting a medium is means for detecting a filling level of said medium in a container.

In an embodiment of the invention said means for detecting a medium is means for detecting the flow of said medium.

In an embodiment of the invention, the means for detecting a medium is means for detecting an aggregation state of the medium.

In an embodiment of the present invention, the means for detecting a medium is a means for detecting a concentration of a substance as a medium in a binary system.

In an embodiment of the invention, the means for detecting a medium is a means for detecting an oil level in the transmission.

The subject of the invention is also the use of the device according to the invention for detecting a medium.

To realize the invention, it is also advantageous to combine the features of the above-described designs, embodiments and claims according to the invention with each other in any arrangement.

Exemplary embodiments of the invention are shown in substantially each of the figures and described in more detail below.

Drawings

In the drawings:

figure 1 shows a block diagram of an apparatus for detecting a medium,

FIG. 2 shows a component carrier as a circuit board of a device for detecting media, an

Fig. 3 shows a device for detecting a medium in connection with a connector housing.

Detailed Description

The device for detecting a medium is mainly composed of a heating sensor 1, a reference sensor 2, and a control device.

Fig. 1 shows a basic block diagram of an apparatus for detecting a medium.

The heating sensor 1 includes at least a first resistor R1 as a heating means, and a p-n junction operating in the forward direction. The p-n junctions are diodes D1-D4 spaced apart from each other in a series circuit.

The reference sensor 2 comprises a p-n junction operating in the forward direction, wherein the p-n junction is designed as diodes D5 to D8 spaced apart from each other and connected in series.

The anodes of the diodes D1 to D4 and the anodes of the diodes D5 to D8 are connected to the DC-DC converter 4 via resistors as second and third resistors R2 and R3, respectively, the DC-DC converter 4 simultaneously being a constant current source for the diodes D1 to D8 operating in the forward direction.

The connection of the second resistor R2 to the anode of the first diode D1 of the heating sensor 1 is connected to the inverting input of the differential amplifier 5. The connection of the third resistor R3 to the first diode D5 of the reference sensor 2 is connected to the non-inverting input of the differential amplifier 5. The values of the second resistor R2 and the third resistor R3 are dimensioned in such a way that the voltage value at the non-inverting input of the differential amplifier 5 is greater than the voltage value at the inverting input of the differential amplifier 5.

The output of the differential amplifier 5 is connected to a data processing system as a control device, this being in particular the microcontroller 3. Which in turn is connected to a resistor R1 that acts as a heating resistor.

By means of the microcontroller 3, the medium and/or at least one property of the medium is ascertained from a temperature-dependent forward voltage generated from a thermal property of the medium.

The voltage supply of the device can take place via a DC-DC converter 4, which DC-DC converter 4 can convert the voltage of the power supply network.

Fig. 2 shows a basic illustration of a component carrier 6 as a circuit board of a device for detecting media.

At least one region of the component carrier 6, which is a circuit board, is designed in a U-shape, wherein the branches for the heating sensor 1 and the reference sensor 2 are finger-shaped. The diodes D1 to D4 and the first resistor R1 in series as a heating resistor for heating the sensor 1 are spaced apart on one leg of the U-shape, while the diodes D5 to D8 for the reference sensor 2 are arranged on the other leg. A microcontroller 3, a differential amplifier 5, and a DC-DC converter 4, each of which is a component, are arranged on the area of the center portion. In addition, a protection circuit may be provided and arranged upstream of the means for detecting the medium.

Fig. 3 shows a basic illustration of the device for detecting a medium in connection with a connector housing.

The branches of the component carrier 6, which are designed in a U-shape, including the specific components, are located in a housing 7, which housing 7 can be, for example, a connector housing. The plug 8 is located on the component carrier 6. Furthermore, a cover 9 comprising an opening can be slid over the housing 7.

Thus, a compact device for detecting a medium is achieved.

In an embodiment, the means for detecting the medium may be

-means for detecting the filling level of the medium in the container,

-means for detecting the flow of the medium,

-means for detecting the state of aggregation of the medium,

means for detecting the concentration of a substance as a medium in a binary system, or

-means for detecting the oil level in the transmission.

The filling level of the medium may be detected for another medium. This is, for example, the filling level of the liquid medium in a container which additionally contains a gaseous medium.

The thermal properties of the flowing medium vary according to the flow rate and thus it is easy to monitor the flow of the flowing medium.

Thus, the means for detecting the aggregation state may be, for example, means for detecting ice in or as water. It is known that water and ice have different thermal properties, which can be used to perform detection by means of said devices.

Depending on the thermal properties of the substance, which can be ascertained by means of the device for detecting the medium, the thermal properties of the binary system can change when the concentration changes. Thus, the concentration of the substance of the binary system can be monitored.

Reference symbols

1 heating sensor

2 reference sensor

3 microcontroller

4 DC-DC converter

5 differential amplifier

6 component carrier

7 casing

8 plug

9 cover

R resistor

D diode